Just picked one up from hobby people, and will chime in here as it gets built.
The first thing I will mention is that I found a use for those funky metal hinges. When installing the aileron servo in one wing, I slipped and pulled the *fish line* out. I tied the fish line to one of the holes in the hinge and dropped it into the aileron hole. Viola!
ORIGINAL: aerobob
The Excelleron has all the guide tubes for the steel cables already installed. Very detailed instructions on how to make it work. Essentially, each elevator half is hooked up just like a normal rudder pull/pull setup works. Each elevator half has a top and bottom cable that goes to the same hole on the servo arm. Just like a rudder, setup with relatively-matched tension on the cables, with control takeoffs the same distance from hinge line.
Pic attached of what the servo end looks like (although not an Excelleron, it's the same idea.
When I saw the above mentioned picture, I ass-u-me'd that this was the stock setup. No, the instructions call for the conventional *trainer-ish* setup of elevator and rudder side by side, and throttle crosswise ahead of them. I like Aerobobs setup better, and I always lay the elevator servo on its side. I have been using this method on a pushrod to split elevator halves to eliminate the need fo MK belcrank. It makes sense for a pull-pull set up too. No twisting of the cables.
I plan to use my tried and true YS.91. I see in this thread that a lot of people are using bigger engines, but I think it should be enough for the intermediate pattern.